- Dump valve
- Wondering about whether I should fit a re-circ type dump valve, vent to atmosphere through filter/silencer.
- I feel a likely position would be here next to the idle control take off, possibly replace that boss
- with a bigger one to feed a dump valve or tee off that to the idle control valve.
Bailey
recirc dump valve.
- Maybe even replace the throttle body hoses with samco T-piece hose with 2 25mm exits to feed the dump valve, that
- would be excellent as it means no major modifications required to the charge cooler.
- Other places could be:-
- On each of the intakes from the turbo's.........I've seen this done already, but don't really want to put them on the hot side of
- the charge cooler and this far away from the throttle bodies.
- Update 27/01/06
- Ok, below pictures of somebody else who already fitted one, which is good as hopefully puts me on
- right path (thanks Paul Mitchell for pictures).
- I settled for a Bailey recirc valve in the end, one reason was to be able to silence the blow off air.
- First I decided to make a flanged adaptor that would bolt to the charge cooler, not as neat as the unit
- fitted above, but at least allowed me more options at a later date with regards different valve and position.
- I had to locate the flange as close as possible to the idle control valve outlet, even then I needed to file away some
- material to make it flat.
- Drilling and tapping M6x1.0 was easy, however swarf did get trapped inside despite efforts to avoid this.
- The actual hole was then chain drilled and finished with a carbide burr tool, a gasket was cut and the flange fitted
- using stainless steel cap head screws.
Perhaps the final fitting for this valve.......not too sure just yet.
Update July 2009
- A while ago I realised that the single piston re-circulating valve was open at idle, whilst not a problem in
- itself, because the other end was venting to atmosphere, it was not ideal. During driving all boost was
- vented between gear change, on off throttle needed time to build boost after each time the valve vented.
- I fitted a twin piston valve, which whilst essentially worked in the same way, during idle the valve was
- closed, also there was residual boost available during gear change, on off throttle was very much more
- responsive. At first I was worried that the trumpet would make the valve operation too loud, I was
- prepared to modify this feature. After driving for a few miles, it became obvious that the noise
- was not a issue at all. When pushed really hard I can hear it, otherwise it's not intrusive at all.
